
Anywho... I have to guiltily admit that I've always been a supporter of the outrageous pairing of Blossom and Dexter... and believe it or not, that was before I ever even read Bleedman's PPGD comic. I'm not delusional in thinking it could ever canonically happen (for one, both shows have been canceled for years), but I always did get the impression that if a Dexter/PPG crossover were to ever take place (which could logically happen, as it has been proven that both series inhabit the same universe), that those two characters might like one another. It's more of a hypothetical sort of thing, since the characters are very similar in several ways. Okay, fine, throw tomatoes at me if you must, but I swear that's the only ship I support that's totally out there. Other than that, I can't say I've ever done any cross-series shipping. That one would be the only exception and most cross-series ships really confuse the heck outta me.
As for shipping in general (as in, characters within the same series), I usually wouldn't ship people that don't even know each other... or, more to the point, I tend to just go with whatever seems to be canon. If there's one thing that's always confused me, it's people that denounce a canon ship (one that the author very obviously intends) in favor of a whack-job ship that makes no sense. Why contradict the author?
I dunno... to me, a lot of shippers out there do seem to be rather insane. Especially the ones that are constantly grasping at straws (hoo-boy, Digimon shippers are notorious for this) to convince people that two characters that are actually indifferent to each other are somehow hiding deep feelings of love for one another. Often times these nut cases will be saying things like, "Look! They're standing next to each other!" or "ZOMG! He asked her a question! He could have asked any of the others, but he didn't! He asked HER! It MUST be love!" (btw, I'm not exaggerating with those, either... those are actually closer to true examples than you might think)